The need for effective means for tilling land has led to a number of power driven rotary tiller configurations, such as those mentioned above, in which a counter rotating rotor was provided for bringing about a heavy mulching action. In that way it was possible to replant a field shortly after the harvesting of the previous crop, by running the rotary tiller over the entire field once. Because of the use of a number of ground-engaging blades or teeth, it was possible to break up encountered clods and vegetation, and achieve a desirable amount of mulching action.
Purchasers of our machines utilized them in a various number of soils and operating conditions, and found that our earlier machines were highly satisfactory in some soil conditions, and less satisfactory in others.
In our above-identified copending patent application, we described the utilization of a toothed rotor interacting with a stationary shear bar, with the rapid rotation of the rotor in the direction opposite the travel of the tiller bringing about a vigorous tilling action as well as the creation of a fluidized soil mass in the upper part of the tiller housing. This brought about a very thorough mixing action, with the resulting mixture being deposited on the ground behind the rotor as it passed along.
Although this action was highly satisfactory in some soils, because sticky soil tended to cling to the interior of the housing, a considerable amount of horsepower was required in the instance in which fields were being worked which contained gumbo or other types of sticky soil. Unfortunately, the volume of the housing of some of our previous machines proved ineffectually small for certain sticky soil conditions, and it was partially in rectification of this earlier construction deficiency that the present design was evolved.